// Tencent is pleased to support the open source community by making RapidJSON available.
// 
// Copyright (C) 2015 THL A29 Limited, a Tencent company, and Milo Yip. All rights reserved.
//
// Licensed under the MIT License (the "License"); you may not use this file except
// in compliance with the License. You may obtain a copy of the License at
//
// http://opensource.org/licenses/MIT
//
// Unless required by applicable law or agreed to in writing, software distributed 
// under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR 
// CONDITIONS OF ANY KIND, either express or implied. See the License for the 
// specific language governing permissions and limitations under the License.

#ifndef RAPIDJSON_PRETTYWRITER_H_
#define RAPIDJSON_PRETTYWRITER_H_

#include "writer.h"

#ifdef __GNUC__
RAPIDJSON_DIAG_PUSH
RAPIDJSON_DIAG_OFF(effc++)
#endif

#if defined(__clang__)
RAPIDJSON_DIAG_PUSH
RAPIDJSON_DIAG_OFF(c++98 - compat)
#endif

RAPIDJSON_NAMESPACE_BEGIN

//! Combination of PrettyWriter format flags.
/*! \see PrettyWriter::SetFormatOptions
 */
enum PrettyFormatOptions {
  kFormatDefault = 0,         //!< Default pretty formatting.
  kFormatSingleLineArray = 1  //!< Format arrays on a single line.
};

//! Combination of PrettyWriter Line Ending flags.
/*! \see PrettyWriter::SetLineEnding
 */
enum LineEndingOption {
  kLf = 0, // default line ending \n
  kCrLf = 1, // \r\n for windows
  kCr = 2 // \r for Mac
};

//! Writer with indentation and spacing.
/*!
    \tparam OutputStream Type of output os.
    \tparam SourceEncoding Encoding of source string.
    \tparam TargetEncoding Encoding of output stream.
    \tparam StackAllocator Type of allocator for allocating memory of stack.
*/
template<typename OutputStream, typename SourceEncoding = UTF8<>, typename TargetEncoding = UTF8<>, typename StackAllocator = CrtAllocator, unsigned writeFlags = kWriteDefaultFlags>
class PrettyWriter : public Writer<OutputStream, SourceEncoding, TargetEncoding, StackAllocator, writeFlags> {
public:
  typedef Writer<OutputStream, SourceEncoding, TargetEncoding, StackAllocator, writeFlags> Base;
  typedef typename Base::Ch Ch;

  //! Constructor
  /*! \param os Output stream.
      \param allocator User supplied allocator. If it is null, it will create a private one.
      \param levelDepth Initial capacity of stack.
  */
  explicit PrettyWriter(OutputStream& os, StackAllocator* allocator = 0, size_t levelDepth = Base::kDefaultLevelDepth) :
    Base(os, allocator, levelDepth), indentChar_(' '), indentCharCount_(4), formatOptions_(kFormatDefault), lineEndingOption_(kLf) {}


  explicit PrettyWriter(StackAllocator* allocator = 0, size_t levelDepth = Base::kDefaultLevelDepth) :
    Base(allocator, levelDepth), indentChar_(' '), indentCharCount_(4), formatOptions_(kFormatDefault), lineEndingOption_(kLf) {}

#if RAPIDJSON_HAS_CXX11_RVALUE_REFS
  PrettyWriter(PrettyWriter&& rhs) :
    Base(std::forward<PrettyWriter>(rhs)), indentChar_(rhs.indentChar_), indentCharCount_(rhs.indentCharCount_), formatOptions_(rhs.formatOptions_) {}
#endif

  //! Set custom indentation.
  /*! \param indentChar       Character for indentation. Must be whitespace character (' ', '\\t', '\\n', '\\r').
      \param indentCharCount  Number of indent characters for each indentation level.
      \note The default indentation is 4 spaces.
  */
  PrettyWriter& SetIndent(Ch indentChar, unsigned indentCharCount) {
    RAPIDJSON_ASSERT(indentChar == ' ' || indentChar == '\t' || indentChar == '\n' || indentChar == '\r');
    indentChar_ = indentChar;
    indentCharCount_ = indentCharCount;
    return *this;
  }
  
  //! Set Line Ending.
  /*! \param lineEndingOption Line ending option
  */
  PrettyWriter& SetLineEnding(LineEndingOption lineEndingOption) {
    lineEndingOption_ = lineEndingOption;
    return *this;
  }
  
  //! Set pretty writer formatting options.
  /*! \param options Formatting options.
  */
  PrettyWriter& SetFormatOptions(PrettyFormatOptions options) {
    formatOptions_ = options;
    return *this;
  }

  /*! @name Implementation of Handler
      \see Handler
  */
  //@{

  bool Null() { PrettyPrefix(kNullType);   return Base::EndValue(Base::WriteNull()); }
  bool Bool(bool b) { PrettyPrefix(b ? kTrueType : kFalseType); return Base::EndValue(Base::WriteBool(b)); }
  bool Int(int i) { PrettyPrefix(kNumberType); return Base::EndValue(Base::WriteInt(i)); }
  bool Uint(unsigned u) { PrettyPrefix(kNumberType); return Base::EndValue(Base::WriteUint(u)); }
  bool Int64(int64_t i64) { PrettyPrefix(kNumberType); return Base::EndValue(Base::WriteInt64(i64)); }
  bool Uint64(uint64_t u64) { PrettyPrefix(kNumberType); return Base::EndValue(Base::WriteUint64(u64)); }
  bool Double(double d) { PrettyPrefix(kNumberType); return Base::EndValue(Base::WriteDouble(d)); }

  bool RawNumber(const Ch* str, SizeType length, bool copy = false) {
    RAPIDJSON_ASSERT(str != 0);
    (void)copy;
    PrettyPrefix(kNumberType);
    return Base::EndValue(Base::WriteString(str, length));
  }

  bool String(const Ch* str, SizeType length, bool copy = false) {
    RAPIDJSON_ASSERT(str != 0);
    (void)copy;
    PrettyPrefix(kStringType);
    return Base::EndValue(Base::WriteString(str, length));
  }

#if RAPIDJSON_HAS_STDSTRING
  bool String(const std::basic_string<Ch>& str) {
    return String(str.data(), SizeType(str.size()));
  }
#endif

  bool StartObject() {
    PrettyPrefix(kObjectType);
    new (Base::level_stack_.template Push<typename Base::Level>()) typename Base::Level(false);
    return Base::WriteStartObject();
  }

  bool Key(const Ch* str, SizeType length, bool copy = false) { return String(str, length, copy); }

#if RAPIDJSON_HAS_STDSTRING
  bool Key(const std::basic_string<Ch>& str) {
    return Key(str.data(), SizeType(str.size()));
  }
#endif

  bool EndObject(SizeType memberCount = 0) {
    (void)memberCount;
    RAPIDJSON_ASSERT(Base::level_stack_.GetSize() >= sizeof(typename Base::Level)); // not inside an Object
    RAPIDJSON_ASSERT(!Base::level_stack_.template Top<typename Base::Level>()->inArray); // currently inside an Array, not Object
    RAPIDJSON_ASSERT(0 == Base::level_stack_.template Top<typename Base::Level>()->valueCount % 2); // Object has a Key without a Value

    bool empty = Base::level_stack_.template Pop<typename Base::Level>(1)->valueCount == 0;

    if (!empty) {
      WriteLineEnding();
      WriteIndent();
    }
    bool ret = Base::EndValue(Base::WriteEndObject());
    (void)ret;
    RAPIDJSON_ASSERT(ret == true);
    if (Base::level_stack_.Empty()) // end of json text
      Base::Flush();
    return true;
  }

  bool StartArray() {
    PrettyPrefix(kArrayType);
    new (Base::level_stack_.template Push<typename Base::Level>()) typename Base::Level(true);
    return Base::WriteStartArray();
  }

  bool EndArray(SizeType memberCount = 0) {
    (void)memberCount;
    RAPIDJSON_ASSERT(Base::level_stack_.GetSize() >= sizeof(typename Base::Level));
    RAPIDJSON_ASSERT(Base::level_stack_.template Top<typename Base::Level>()->inArray);
    bool empty = Base::level_stack_.template Pop<typename Base::Level>(1)->valueCount == 0;

    if (!empty && !(formatOptions_ & kFormatSingleLineArray)) {
      WriteLineEnding();
      WriteIndent();
    }
    bool ret = Base::EndValue(Base::WriteEndArray());
    (void)ret;
    RAPIDJSON_ASSERT(ret == true);
    if (Base::level_stack_.Empty()) // end of json text
      Base::Flush();
    return true;
  }

  //@}

  /*! @name Convenience extensions */
  //@{

  //! Simpler but slower overload.
  bool String(const Ch* str) { return String(str, internal::StrLen(str)); }
  bool Key(const Ch* str) { return Key(str, internal::StrLen(str)); }

  //@}

  //! Write a raw JSON value.
  /*!
      For user to write a stringified JSON as a value.

      \param json A well-formed JSON value. It should not contain null character within [0, length - 1] range.
      \param length Length of the json.
      \param type Type of the root of json.
      \note When using PrettyWriter::RawValue(), the result json may not be indented correctly.
  */
  bool RawValue(const Ch* json, size_t length, Type type) {
    RAPIDJSON_ASSERT(json != 0);
    PrettyPrefix(type);
    return Base::EndValue(Base::WriteRawValue(json, length));
  }

protected:
  void PrettyPrefix(Type type) {
    (void)type;
    if (Base::level_stack_.GetSize() != 0) { // this value is not at root
      typename Base::Level* level = Base::level_stack_.template Top<typename Base::Level>();

      if (level->inArray) {
        if (level->valueCount > 0) {
          Base::os_->Put(','); // add comma if it is not the first element in array
          if (formatOptions_ & kFormatSingleLineArray)
            Base::os_->Put(' ');
        }

        if (!(formatOptions_ & kFormatSingleLineArray)) {
          WriteLineEnding();
          WriteIndent();
        }
      }
      else {  // in object
        if (level->valueCount > 0) {
          if (level->valueCount % 2 == 0) {
            Base::os_->Put(',');
            WriteLineEnding();
          }
          else {
            Base::os_->Put(':');
            Base::os_->Put(' ');
          }
        }
        else
          WriteLineEnding();

        if (level->valueCount % 2 == 0)
          WriteIndent();
      }
      if (!level->inArray && level->valueCount % 2 == 0)
        RAPIDJSON_ASSERT(type == kStringType);  // if it's in object, then even number should be a name
      level->valueCount++;
    }
    else {
      RAPIDJSON_ASSERT(!Base::hasRoot_);  // Should only has one and only one root.
      Base::hasRoot_ = true;
    }
  }

  void WriteIndent() {
    size_t count = (Base::level_stack_.GetSize() / sizeof(typename Base::Level)) * indentCharCount_;
    PutN(*Base::os_, static_cast<typename OutputStream::Ch>(indentChar_), count);
  }

  void WriteLineEnding() {
    switch (lineEndingOption_) {
    case kCrLf:
      Base::os_->Put('\r');
      Base::os_->Put('\n');
      break;
    case kCr:
      Base::os_->Put('\r');
      break;
    default:
      Base::os_->Put('\n');
      break;
    }
  }

  Ch indentChar_;
  unsigned indentCharCount_;
  PrettyFormatOptions formatOptions_;
  LineEndingOption lineEndingOption_;

private:
  // Prohibit copy constructor & assignment operator.
  PrettyWriter(const PrettyWriter&);
  PrettyWriter& operator=(const PrettyWriter&);
};

RAPIDJSON_NAMESPACE_END

#if defined(__clang__)
RAPIDJSON_DIAG_POP
#endif

#ifdef __GNUC__
RAPIDJSON_DIAG_POP
#endif

#endif // RAPIDJSON_RAPIDJSON_H_
